Layer Cakes are 10 inch squares containing fabrics from a specific collection or coordinating quilting fabrics. There are 42 squares in one Layer Cake.
The pre cut squares allow the quilter to have a great selection and reduce cutting time. Many quilting patterns call for using the 10 inch squares.
Thus the advantage is you are buying a great selection of fabrics the same size. Plus the quilter does not need to buy 1/2 yard of each fabric if this much is not needed.
What can you do with a 10 inch square? Cut in half twice to make 5 inch squares. Cut each diagonally once to yield (2) 9 inch finished half square triangles. There are many more possibilities with this versatile size.
The importance is the accuracy of the cuts you receive. This is a huge time saver for you. Layer Cakes are packaged by the manufacturer or custom made by the seller.